The present disclosure relates generally to displays for electronic devices. Specifically, the embodiments described herein generally relate to using pixel data voltages to account for errors in one or more common voltages within a display.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Electronic displays may be found in a variety of devices, such as computer monitors, televisions, instrument panels, mobile phones, and clocks. One type of electronic display, known as a liquid crystal display (LCD), displays images by modulating the amount of light allowed to pass through a liquid crystal layer within pixels of the LCD. In general, LCDs modulate the light passing through each pixel by varying a voltage difference between a pixel electrode and a common electrode. This creates an electric field that causes the liquid crystal layer to change alignment. The change in alignment of the liquid crystal layer causes more or less light to pass through the pixel. By changing the voltage difference supplied to each pixel, images are produced on the LCD.
In some LCDs, the value of the common voltage may vary across the LCD. For example, in some LCDs, the display panel may be composed of sub-plates associated with different respective groups of pixels. Variations in the amounts of electromagnetic cross-talk caused by differences in the sub-plates and/or electromagnetic noise from other electronic components near the LCD may cause the common voltage to settle to different final values across the LCD. A block mura artifact may arise when the common voltage is a different value for each sub-plate, thereby causing all of the pixels associated with each sub-plate to be different by some discernible brightness, and thereby producing visible blocks of brighter or darker pixels.
One method to reduce this effect may involve lowering the coupling capacitance between the signal lines for the common voltage and the source voltages. For example, specific placement and routing of the signals lines for the common voltage and the source voltages may be developed to reduce the capacitance between the signal lines. However, there may be limited areas for routing in an LCD, and, as mentioned above, the panel impedance may vary from sub-plate to sub-plate as well as across a given sub-plate. In other techniques, the display controllers and drivers may include a negative feedback system to correct the value of the common voltage. That is, a negative feedback system may be included for each sub-plate, which may sense the value of the common voltage at the sub-plate and send the corresponding data to the common voltage source. However, the negative feedback systems may increase the space requirements of the display.